Structure optimization for continuous production systems with buffers under reliability constraints

A problem of structure optimization of a series-parallel production system is considered where redundant producing elements (machines) and in-process buffers are included in order to provide a desired level of reliability. A procedure which determines the minimal cost system configuration is proposed. In this procedure, producing elements and buffers are chosen from a list of products available in the market. The elements are characterized by their cost, estimated average up and down times and productivity (machines) or capacity (buffers). System reliability is defined as the ability to satisfy consumer demand which is represented by a piecewise cumulative load curve. A genetic algorithm is used as an optimization technique. An example of the redundancy optimization of a power station coal feeding system is presented.